how to build a dual_arm system in Gazebo and MoveIt?

enter code here I tried to build a dual-arm system by iiwa. I downloaded code on Github, the name of package is:"iiwa_stack" website:https://github.com/IFL-CAMP/iiwa_stack Then, I wrote a xacro file to include the model of iiwa7 twice. And named them as "`iiwa_Left`" and "`iiwa_Right`" There is my xacro file: Gazebo/White Then, I wrote a new gazebo.launch file. You can see that, left and right arm use different control.launch file in different namespace. I think two arms should in different namespace. The file `dual_iiwa_world.launch` is same to the origin file `"iiwa_world.launch"`, I just changed the model file. There is my gazebo.launch file. Next, I use moveit_setup_assistance to set the dual_arm model. I put two arms in different planning group. Then I put both of groups in one planning group as two subgroups.Like this.  Finally, I imitate the origin moveit_planning_execution.launch, I wrote a new one.[$(arg robotL_name)/joint_states][$(arg robotR_name)/joint_states] I had tried build two name space `iiwaLeft` and `iiwaRight` to include move_group.launch, but it had seemed doesn't work. So i tried build one name space `dual_iiwa`. But i didn't work all the same. The problem is that, I can plan and execute two arms in Rviz, but in Gazebo, dual_arm didn't move. I think there may be something wrong with my namespace or I use the move_group.launch in a wrong way.